jamesp
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Post by jamesp on Jan 20, 2024 15:17:49 GMT -5
Melt above. Made a boo boo, forgot to put the 3/16" ceramic felt around the inside of brickmold. Well, glass expands when it solidifies, and it did just that requiring hammerized removal. NO other way to remove. Live/learn. Great tumbling fodder, oh well. Or cab fodder if anyone wants to give it a go for a cab just say. Used a bit too much dark glass. Brick, and the expansion sent fractures. Mold is strong/rigid/unbendable/etc: Hammered results, quite psycho. get back fordite !: Down the inverted volcano pour point: misc chips
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jamesp
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Post by jamesp on Jan 19, 2024 12:53:48 GMT -5
This one should be a wild thang. Even poured it thru a smaller hole to increase mixing. In anneal mode till tonight.
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jamesp
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Post by jamesp on Jan 19, 2024 12:44:55 GMT -5
Will be trying to repeat this 2018 pour. Used a smaller hope in the pour bowl and raised the bowl higher. Somehow the glass poured in thin stream that spiraled as it accumulated and piled in the mold, it also squashed outwardly. The complete dynamics remain a mystery. Note how glass color changes after fusion: Note how colors stayed in order down pontil pipe, but note spiral landing in mold: slabs slabs closer up, more complex up close: tumbled but wet: Trying to coax rockbrain to get a glass kiln...
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jamesp
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Post by jamesp on Jan 19, 2024 12:27:34 GMT -5
Doing a great job my friend! Thanks fossilman.
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jamesp
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Post by jamesp on Jan 19, 2024 12:26:51 GMT -5
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jamesp
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Post by jamesp on Jan 16, 2024 15:41:33 GMT -5
Another tribal pattern did as planned. A thinner arrowhead will reveal the translucent purple glass better than a 5/16" thick slab. backlit
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jamesp
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Post by jamesp on Jan 16, 2024 15:33:32 GMT -5
Knowing nothing about glass fusing, I am curious if the piece with the fractures couldn't be saved? Could you not reheat it slowly to the point where the glass melts enough to fuse together all the fractures? Or can you not get the glass fluid enough for the fractures to properly heal? Maybe the air in the fractures cant "bubble" out so there will still be defects? Inquiring minds what to know! To save energy two bowl/brick melts were performed simultaneously. Peak temp(1475F) dwell time was raised from 3 hours to 4 hours to assure kiln would not struggle to melt 25 pounds total glass. The above brick being brown and black glass could handle the extra heat. However the red glass in the other brick suffered from too much heat and fractured trashing 11 pounds of glass grrr. At raw glass cost of about $15/pound it is good that I acquired this glass very cheap. Has cracks throughout(trash): Herb this glass gets brittle when remelted. It casts one shot excellent. It is not a high quality fusing glass in that way, but it makes very strong glass that rarely fractures upon cooling in thick blocks. Analogy, large and powerful but not quick and nimble. Glass has many trade-offs too. Attempt to take obsidian to fuse/melt temps and most of it will convert to pumice, something in the composition makes it fizzle air bubbles intensely.
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jamesp
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Post by jamesp on Jan 14, 2024 14:20:28 GMT -5
Deep Purple pour brick in kiln today. I'm a sucker for that purple! LOL! You and me both Tela. Such royal purple tickles eyes. Dark purple glass is often used as black glass(you probably know having worked glass). If memory serves a form of cheap iron or perhaps manganese turns glass purple. The sand in NE Florida(manganese rich) makes clear glass that often turns purple when exposed to the elements. The China load came with lots of this near black purple glass. The arrowhead guys should like making some thin points that reveal the purple color depth. I'd prefer to find a giant vein of large amethyst crystals with such color !
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jamesp
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Post by jamesp on Jan 14, 2024 8:32:18 GMT -5
Deep Purple pour brick in kiln today.
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jamesp
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Post by jamesp on Jan 14, 2024 8:25:30 GMT -5
I'll be interested to see what you make with this. I hope this works out well for you. Thank you much rockbrain. This was about the only affordable choice. Shoulda added lavender and purple to complete the natural spectrum. This comes in 7mm-10mm rods, could get cheaper if bought in plates or bricks. Consider the rods offer a whole different dimension in patterns. Certain I will be tooting my horn by posting photos .
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jamesp
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Post by jamesp on Jan 13, 2024 9:53:10 GMT -5
Hmmm, opaque glass rods from China. Getting an Alibaba quote. Let's see how placing a China order fares. American glass rod is probably $200/kilogram. China selling for $6.99 TO $9.99/kilogram. Certainly cheaper. Pricing makes sense, 6.99 for cheaper blue and green colors, 8.99/9.99 for costlier yellow/orange/red colors. Did a sample quote for 180 kilograms(see order in photo below). So 400 pounds of rods cost $1518.20. Shipping via sea is $820(China to Atlanta USA freight terminal for me to pick up). Total cost would be like $2340. Ship time slow, March 8 - March 20. 400 pounds makes about 40 bricks selling at $200/brick totalling $8000. Enough to support a hobby, no get rich quick scheme. Melting rods would present some unique patterns.
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jamesp
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Post by jamesp on Jan 13, 2024 9:24:56 GMT -5
To save energy two bowl/brick melts were performed simultaneously. Peak temp(1475F) dwell time was raised from 3 hours to 4 hours to assure kiln would not struggle to melt 25 pounds total glass. The above brick being brown and black glass could handle the extra heat. However the red glass in the other brick suffered from too much heat and fractured trashing 11 pounds of glass grrr. At raw glass cost of about $15/pound it is good that I acquired this glass very cheap. Has cracks throughout(trash):
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jamesp
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Post by jamesp on Jan 12, 2024 11:13:34 GMT -5
Had lemon yellow glass been used with the black the patterns would likely be different RickB.
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jamesp
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Post by jamesp on Jan 10, 2024 15:23:15 GMT -5
Poured from a bowl into a brick mold. Poured a whole 14 pounds of glass(normally they are 10 pounds, brick about 11x6x1.6 inches). Black glass is actually dark brown, other is tan, both probably loaded with iron and strong tough glass. Tribal pattern, almost dendritic flow. Lower photo is cut thru where glass poured in. The glass was stacked in the bowl in alternating colors. It flowed thru the hole like brown and black balloons inside of each other(more obvious in upper photo) which is mysterious. More glass was added in the bottom of the bowl per color and less as filling bowl thinking that the first balloon to fill the mold is larger, but the smaller balloons are thicker. Could have been a theory of vanity...an upside down volcanic obsidian flow into a brick mold comes to mind. Two 1/4's of the whole brick
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jamesp
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Post by jamesp on Jan 9, 2024 16:29:49 GMT -5
Think Fordite or "damascus glass". Perhaps a tightly banded agate slab. Stack began with 16 colors 1/8" thick = 2". Stack was 4"x 9" before melt. After, the melt puddle is reduced to 5/8" thick and about 16" diameter but still has 16 color bands. Poor man's Fordite ? So technique is similar to a Fordite cab to reveal layers on dome slope, but in this case layers would be revealed as arrowhead is knapped from it. However arrowhead would be schitzo because one side would have different colors than the other. Or it could be fused 8 colors on top half and same 8 colors on bottom half. Glass laminated like this is extremely strong. Rings like a stiff bell when two halves are tapped together. Perfect for long skinny spearheads. Need to get some of you cabbers playing with this stuff.
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jamesp
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Post by jamesp on Jan 8, 2024 12:38:57 GMT -5
Unique Horse Creek chert in cobble form NE AL/SW TN.
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jamesp
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Post by jamesp on Jan 8, 2024 12:31:30 GMT -5
That is a slippery slope of some seriously talented folks. Lol.
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jamesp
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Post by jamesp on Jan 8, 2024 8:52:46 GMT -5
You should delve into making points rockbrain. Best to search "heat treating flint"(or agate, chert, jasper) to increase 'knap-ability'. If cooking rock in soil it is best to do it on low wind days so the fire burns at consistent heat and to avoid temp spikes. Or talk to master knapper RickB. His points are to cry for. Cooking Native American(tenets of Shem) style
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jamesp
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Post by jamesp on Jan 4, 2024 7:16:53 GMT -5
jamesp Good looking glass bricks, even the ones that did not quite come out. Also good to see you active and posting again, your posts with pictures are always a favorite of mine. Stay busy my friend. Henry I call this one the atom bomb pattern Henry. It took several attempts to duplicate from back in 2018. Couldn't remember the recipe. Instead of having a 5 inch stack using 1/8" of each color it took a 5 inch stack using 1/4" of each color to get the defined color banding to not mix with each other. These stacks would be laid into an 11" Ikea stainless salad bowl with a 1.5" pour hole in the bottom of the bowl. Bowl hole about 1.5" above the brick mold. Changing the hole size or the pour bowl height makes for a different outcome. Pouring from higher causes more mixing. Smaller pour hole makes for more mixing. These mechanical dimensions were established back in 2018, it was the stacking of the glass that was forgotten. Anyway, this was yesterday's pour. Sawed 10x6x1.75 inch brick into 3 sections and they were sold on FB arrowhead maker's site(Art of Flint Knapping) within 10 minutes. These guys are making arrowheads out of a wider variety of agates and cherts these days, worth a visit. The materials they use have to be tough and fracture free, good rugged stuff for tumbling and cabbing. 3 colors of green, light clear green, opal tennis ball green and darker clear green. Note jagged accordion effect. No idea why this happens. Back lit so the clear greens can be seen
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jamesp
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Post by jamesp on Jan 4, 2024 6:30:14 GMT -5
Thanks pebblesky. with a bunch of colors it doesn't take too much effort.
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